Exteriorly cooled furnace roller assembly



United States Patent [72] inventor Rolland L. Homnan Upper St. Clair Township, Allegheny County, Pennsylvania [21 Appl. No. 798,007

[22] Filed Feb. 10, 1969 [45] Patented Nov. 17, 1970 [73] Assignee Bloom Engineering Company, Inc.

Pittsburgh, Pennsylvania [54] EXTERIORLY COOLED FURNACE ROLLER Primary Examiner-John J. Camby Attorney-Webb, Burden, Robinson and Webb ABSTRACT: An exteriorly cooled roll assembly comprising a closed water jacket extending transversely through a furnace, a driven shaft extending coaxially within the water jacket and through the ends thereof and a series of discs concentrically disposed about the shaft and having a small section of each disc extending through slot openings in the top of the water jacket to support the workpiece. Bearing supports are positioned within the water jacket under each disc to bear the weight of the workpiece. Additional supports can be employed in alignment with the bearing supports and exterior to the water jacket.

Patented Nov. 17,1970

INVENTOR. Rolland L.H0ffman M, M Mi Fig. 2

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HIS ATTORNEYS Patented Nov. 11, 1970 Sheet Fig. 6

INVENTOR. Rolland L. Hoffman WM M flw m a HIS ATTORNEYS EXTERIORLY COOLED FURNACE ROLLER ASSEMBLY veyors employed are often exposed to elevated temperatures over 2000F. and must sustain loads often in excess of 20 tons. Because of the load requirements, large load carrying rolls are employed which must be sufficiently cooled to operate effectively within the furnaces. This has generally been accomplished by using rolls with hollow interiors of various constructions and passing water therethrough in various manners. As the load requirements of the rolls, which are supported at their ends exteriorly to the furnace, is increased the size of the roll is increased, thus increasing the problem of cooling the rolls.

My invention overcomes these problems by eliminating the large interiorly cooled rolls. Because the large interiorly cooled rolls are eliminated, there is virtually no limit on furnace temperature as a result ofthe common limitating roll factors known heretofore. My invention further eliminates the cumbersome roll designs, thus permitting ease of maintenance and part replacement. My invention does not rely on a rotating roll to carry the load and, therefore, the only design requirement is based on the torque requirement to drive'the load through the furnace. Because of the simplicity and small relative size of my invention, it is more easily protected from the furnace heat.

My invention is an exteriorly cooled roll system. A driven shaft extends through a closed water jacket which in turn extends transversely through a furnace. A series of load carrying discs are concentrically positioned about the shaft, and a small section of each disc extends out of slot openings in the top of the water jacket to support the workpiece. Vertical bearing supports are positioned below the discs within the water jacket to support the load'.

In the accompanying drawings, I have shown my presently preferred embodiments of my invention in which:

FIG. 1 is a section through a metallurgical furnace containing my roll assembly;

FIG. 2 is a section along section lines II-II of FIG. 1;

FIG. 3 is a section along section lines III-III of FIG. 1;

FIG. 4 is a section along section lines IV-IV of FIG. 1;

FIG. 5 is a section through another embodiment of my invention in a metallurgical furnace; and I FIG. 6 is a section through section lines VI-VI of FIG. 5.

l have shown my exteriorly cooled roll assembly 1 positioned in a metallurgical furnace 2 having refractory walls 3, a domeshaped refractory roof 4 and a refractory floor 5 (FIG. 1). A series of burner ports 6 are positioned in the furnace walls 3 to accommodate burners (not shown) for heating the furnace 2. A series ofsimilar rolI assemblies 1 are transversely positioned in the furnace in parallel spaced apart relationship to convey the workpieces such as slab 7; however, I have shown just one such roll assembly 1 for ease of presentation.

A closed steel plate water jacket 8 extends transversely through the furnaceand through accommodating openings 9 in the opposite furnacewalls 3. Within the interior of the furnace 2, the water jacket 8 is completely covered with an insulating material 10 such as a high temperature castable refractory to withstand the furnace temperature and minimize any temperature loss to the furnace due to the water jacket 8. The top surface 11 of the water jacket 8 has a series of spaced slot openings 12 within the interior of the furnace and extending through the insulant 10. Sections 16 and 17 of water jacket 8 extend through the furnace walls 3 exterior to the furnace and are supported by L-shaped support members 13 which in turn are supported by the superstructure (not shown). Section 16 of the water jacket 8 has a water inlet 14 for connection to a water source and section 17 has a water outlet 15 for exiting the water so that water can be circulated through the water jacket 8. Simple overflow openings. (not shown) well known in the art positioned at the end'of either section 16 or 17 or both provide an automatic water lever control to maintain the proper level of water in jacket 8.

A shaft 20 adaptable for rotation extends through the water jacket 8 and the furnace 2. One end 21 of shaft 20 extends through a shaft opening 18 in section 16 of water jacket-8 and is driven by drive mechanism 22 attached thereto. Rotary ring seal 19 is positioned about shaft 20 at shaft opening 18 in section 16 of water jacket 8 to maintain a proper seal and prevent leakage of water from the water jacket 8. The shaft 20 is supported exteriorly to the furnace 2 by journal bearings 25 supported by casting 26 mounted within sections 16 and 17 of water jacket 8 by means of bolts 27 secured ,to the floor 23 of the water jacket 8 and positioned over L-shaped supports 13 (FIG. 3).

A series of discs 28 are concentrically disposed about shaft 20 in spaced apart relationship within the interior of the furnace 2. These discs are spaced so that they are aligned with the slot openings 12 in water jacket 8 and a small section of mounted to the floor 23 of the water jacket 8, mounting not shown (FIG. 4). Extending upward from base 31 are supports 32 whichaccommodate bearing shaft 33. The base 31, supports 32 and bearing shaft 33 form a housing for bearing 34. The support and base can, of course, be a single casting. Bearing 34 (shown schematically) is positioned about shaft 33 and in contact with disc 28. Bearing 34 can be oh variety of kinds well known in the art. Each bearing assembly 30 has two parallel bearing shafts 33 and bearings 34 mounted thereon to contact disc 28 on the opposite sides of the lower half of disc 28 (FIG. 4). The bearing assembly is the load carrying support for the slab 7 and in turn is supported by the water jacket 8 which is supported external to the fumace'by L-shaped supports 13.

Where very heavy loads are conveyed through the furnace 2 or where the furnace is exceptionally wide, it may be desirable to add additional load carrying supports. I have shown such additional supports in FIGS. 5 and 6. Parts similar to the earli er embodiments are given the same numerals but are followed by a prime. The water jacket 40 has protruding sections 41 extending outward from the water jacket (FIG. 6) to accommodate the discs 28' and the bearing assembly 30', both of which are larger than the respective disc 28 and bearing assembly 30 of the earlier embodiment. These sections 41 also extend downward from the water jacket to likewise accommodate the large sizing of the aforementioned parts (FIG. 5). Hollow walled tubular support members 42 extend vertically downward from the floor 23 of section 41 through thefurnace 2 and furnace floor 5 and into the substructure or substratum of the building (not shown) housing the furnace. Within the furnace 2', support members 42 are covered with insulant 10'. Water circulating means 43 positioned below the furnace cooperate with the hollow tubular walls to circulate a coolant such as water therethrough, thereby cooling the support structure 42 from the heat of the furnace. The insulant 10' covers the support members 42 to protect members 42 and to prevent the furnace from being cooled by the coolant circulating through the member.

The operation of the exteriorly cooled furnace roller assembly is as fo llows water is circulated through the water jacket 8. The water is maintained at a level just below the top surface of the slot openings 12. The slab 7 is conveyed on discs 28 which are concentrically disposed about rotating shaft and which protrude through slot openings 12 in the top of furnaces.

The weight of the slab is born by the bearing assembly positioned under the discs 28 which in turn is born by the water jacket 8 supported exteriorly to the furnace by supports 13. Additional members 42 which are aligned with the bearing assembly 30 and which extend vertically downward from waterjacket floor 23 through the furnace can be employed to add additional support where required.

Some water in the waterjacket will, of course, vaporize and pass into the furnace through the slot openings. However, this water vapor will be carried off through the flues of the furnace (not shown) with the water vapor created by the combustion of any hydrocarbon fuel.

While I have shown and described the presently preferred embodiments of my'invcntion, it may be otherwise embodied within the scope ofthe appended claims.

l claim: I. An exteriorly cooled roll assembly for a furnace comprising:

A. At least one stationary closed coolant jacket extending transversely through a furnace and having coolant inlet and outlet means to circulate coolant therethrough and having at least two slot openings in the top thereof within the furnace, said coolant jacket having a shaft opening at at least one end thereof;

B. A shaft longitudinally extending through the coolant jacket and the shaft opening and supported at substantially the ends thereof by first support means;

C. Drive means connected to the shaft to cause rotation thereof;

D. At least two discs concentrically disposed about the shaft to support a workpiece, said discs aligned with the slot openings so that a small section of each disc extends through each of said slot openings; and

E. Second support means positioned within the coolant jacket to support at least one of said discs.

2. The roll assembly of claim 1 wherein said second support means each of said discs disposed about the shaft.

3. The roll assembly of claim 1 wherein the second support means is two vertical support bearing means mounted on respective shafts' which are rotatably mounted to a housing secured to the bottom of the coolant jacket, said bearing means contacting the disc and rotating therewith to support said disc when a workpiece is being conveyed thereover.

4. The roll assembly ofclaim 1 wherein the coolantjacket is supported exteriorly to the furnace.

5. The roll assembly of claim 1 wherein an insulant surrounds the watcrjacket within the furnace.

6. The roll assembly of claim 1 wherein seal means cooperate with the shaft opening of the coolant jacket to prevent leakage of coolant between the shaft opening and the shaft.

7. The roll assembly of claim 1 wherein the first support means is a bearing support concentrically positioned about said shaft and contained within the coolant jacket and supported by third support means exterior to the coolantjacket.

8. The roll assembly of claim 1 wherein water is the coolant.

9. The roll assembly of claim 1 wherein coolant overflow means are positioned at either end of the coolant jacket to maintain the coolant at the desired height within the coolant jacket.

10. The roll assembly of claim 1 wherein fourth support means exterior to the waterjacket extend vertically downward from the waterjackct through the bottom ofthc furnace.

11. An exteriorly cooled roll assembly for a furnace comprising:

A. A stationary closed water jacket extending transversely through a furnace and having water inlet and outlet means to circulate water therethrough and having at least two slot openings in the top thereof within the furnace, said water jacket having a shaft opening at at least one end thereof; B. A shaft longitudinally extending through the water jacket and the shaft opening and supported at substantially the ends thereof by concentrically disposed first bearing means;

C. Drive means connected to the shaft at one end thereof to cause rotation thereof;

D. At least two discs concentrically disposed about the shaft to support a workpiece, said discs aligned with the slot Openings so that a small section of each disc extends through each of said slot openings;

E. At least two second bearing means positioned within the water jacket, each of said second bearing means aligned under each of the discs to support said discs when a workpiece is supported thereon; and

F. At least two support members positioned exterior to the water jacket and extending vertically therefrom through the bottom of the furnace, each support member in alignment with each of said second bearing means.

12. The exteriorly cooled roll assembly of claim 11 wherein an insulant surrounds the support members within the furnace.

13. The exteriorly cooled roll assembly of claim 12 wherein the support members have hollow walls extending thereabout and a water inlet and outlet connected to the hollow walls to circulate water therethrough.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, a a D t d November 17, 1970 Inventor(x) Rolland L. Hoffman It is certified that: error appears in the above-1dent1f1ed patent and that said Letters Patent are hereby corrected as shown below:

Column 1 Line 66 --tempera.ture-- should read --tempera.tures--. Column 2 Line 51 --embodimenta-- should read -embodiment--. Claim 2 Column 3 Line 40 --means each-- should read --means supports ea SIGNED AND SEALED FEB 2M (SEAL) 

